The standard of living of modern society relies heavily on economical access to semiconductors and integrated circuits. In turn, the manufacture of semiconductors requires access to high purity silicon, and thus improved processes and systems for the manufacture of high purity silicon is of tremendous value.
Semiconductor grade polysilicon must be extremely pure or semiconductors and photovoltaic cells made therefrom do not provide optimal operability. The Siemens process is utilized in many commercial plants for the preparation of ultrapure polysilicon. In the Siemens process, high purity silicon rods are exposed to trichlorosilane (HSiCl3, TCS) at about 1150° C. The TCS gas decomposes and deposits additional silicon onto the rods. This process produces extremely pure silicon, also called polysilicon or polycrystalline silicon, having impurity levels of less than one part per billion when the process is performed under optimal conditions. The Siemens process can be described by the chemical reaction:4HSiCl3=>Si+3SiCl4+2H2 
As shown by the above equation, silicon tetrachloride (SiCl4, STC) is a byproduct of the Siemens process. In fact, STC is a byproduct that is generated in significant amounts, and it is essentially a waste material. The successful and economical conversion of STC into a useful material is essential in order for the Siemens process to operate in an economic and environmentally friendly manner. One option is to convert STC back into TCS, where TCS can enter into the Siemens process. In fact, various processes to achieve that goal have been described. The present invention provides an improved process for achieving that result.